CVEvulnerability

CVE-2026-28490

8.3 HIGH Published 2026-03-16 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-03-16
Last modified
2026-06-17
Assigner
[email protected]
CVSS 4.0 ([email protected])
8.3 HIGH — CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1 ([email protected])
6.5 MEDIUM — CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
Weaknesses
CWE-203, CWE-327

Description

Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to version 1.6.9, a cryptographic padding oracle vulnerability was identified in the Authlib Python library concerning the implementation of the JSON Web Encryption (JWE) RSA1_5 key management algorithm. Authlib registers RSA1_5 in its default algorithm registry without requiring explicit opt-in, and actively destroys the constant-time Bleichenbacher mitigation that the underlying cryptography library implements correctly. This issue has been patched in version 1.6.9.

Affected configurations

• authlib authlib (< 1.6.9)

Related

Weakness · CWE (2)

  • CWE-203 Observable Discrepancy weakness
  • CWE-327 Use of a Broken or Risky Cryptographic Algorithm weakness

References